IP phone is a type of phone that uses internet or other network with Internet Protocol to transmit phone calls. Voice over Internet Protocol (VoIP) is an IP phone-based technology including corresponding value-added services. The VoIP, mainly featured of a low communication cost, effective construction cost, easy expandability, and better communication quality, and so on, is regarded as a strong competitor of the traditional telecom service by international telecom companies. At present, with the growing number of mobile devices used by consumers, it is difficult for consumers to manage the increasing phone numbers. Moreover, in the traditional calls, the disclosure of real phone numbers causes a lot of problems.